# Fixed Timestamp Datatype

Fixed timestamps represent an exact point on the time-line, limited to millisecond precision, encoded as ISO8601 Times, with a timezone offset. The timezone offset returned will always be expressed in UTC (Coordinated Universal Time), with a special UTC designator (“Z”). For example:

When writing data, accuracy to only the second is required, but the service will always return precision to the millisecond. Additionally, you can use offsets like -0800 (or -08:00). Using this offset system, America/Los_Angeles is expressed as UTC-08:00, or UTC-07:00 in the summer. The offset -08:00 indicates that America/Los_Angeles time is obtained from UTC by adding -08:00, that is, by subtracting 8 hours. Accordingly, 2020-10-16T18:00:00.000Z and 2020-10-16T10:00:00.000-0800 are two different but equally valid representations of the same fixed_timestamp value.

If you are a data publisher, please note that the SODA Producer API converts values with non-UTC offsets into the equivalent UTC representation of the value, so if you write a value like 2020-10-16T10:00:00.000-0800 to a fixed_timestamp field, the SODA Consumer API will return that value as 2020-10-16T18:00:00.000Z.

The following operators can be used to compare and manipulate fixed_timestamp fields:

Operator Description
< TRUE when the first date is earlier than the second date
<= TRUE when the first date is earlier than or at the same time as the second date
> TRUE when the first date is after the second date
>= TRUE when the first date is after or at the same time as the second date
!= TRUE when two dates are not at the same time
= TRUE when two dates are at the same time
IS NULL TRUE for dates that are NULL.
IS NOT NULL TRUE for dates that are not NULL.

And the following functions can be used to filter and manipulate them:

Keyword Name Description Availability
distinct Returns distinct set of records 2.1
Function Name Description Availability
between ... and ... Returns TRUE for values in a given range 2.1
case(...) Returns different values based on the evaluation of boolean comparisons 2.1
count(...) Returns a count of a given set of records 2.0 and 2.1
in(...) Matches values in a given set of options 2.1
max(...) Returns the maximum of a given set of numbers 2.1
min(...) Returns the minimum of a given set of numbers 2.1
not between ... and ... Returns TRUE for values not in a given range 2.1
not in(...) Matches values not in a given set of options 2.1

For example, to get all of the rows that were created before October 16, 2020 at 06:00:00 AM, we can query on the :created_at system field, which is a fixed_timestamp type:

https://soda.demo.socrata.com/resource/6yvf-kk3n.json?\$where=:created_at < '2020-10-15T03:00:00.000Z'

Text strings will be automatically be cast when used in comparisons, as shown above.